Our power went off and on while the computer was on, but the monitor was not on yet. Now when I turn the computer on, the monitor says, "no input signal, check cables" All of the cables are plugged in. So my question is, is it the monitor or the video card that is on the fritz?

hello,

Do you have a laptop to test if the monitor is working?
Do you have a dedicated graphics card, on board or both? If you have both try removing the dedicated graphics card and try the on board one.

Did you hear any beeps when you turn the PC on?
Does your PC sound like it is booting up as normal?